33863-77-3Relevant academic research and scientific papers
Enhanced Hydride Donation Achieved Molybdenum Catalyzed Direct N-Alkylation of Anilines or Nitroarenes with Alcohols: From Computational Design to Experiment
Huang, Ming,Huang, Yong-Liang,Ke, Zhuofeng,Lan, Xiao-Bing,Li, Weikang,Liu, Jiahao,Liu, Yan,Ye, Zongren,Zhao, Cunyuan
, p. 10377 - 10382 (2021/08/31)
An example of homogeneous Mo-catalyzed direct N-alkylation of anilines or nitroarenes with alcohols is presented. The DFT aimed design suggested the easily accessible bis-NHC-Mo(0) complex features a strong hydride-donating ability, achieving effective N-alkylation of anilines or challenging nitroarenes with alcohols. The enhanced hydride-donating strategy should be useful in designing highly active systems for borrowing hydrogen transformations.
Photocatalytic Water-Splitting Coupled with Alkanol Oxidation for Selective N-alkylation Reactions over Carbon Nitride
Xu, Yangsen,Zhang, Zhaofei,Qiu, Chuntian,Chen, Shaoqin,Ling, Xiang,Su, Chenliang
, p. 582 - 589 (2020/12/09)
Photocatalytic water splitting technology (PWST) enables the direct use of water as appealing “liquid hydrogen source” for transfer hydrogenation reactions. Currently, the development of PWST-based transfer hydrogenations is still in an embryonic stage. Previous reports generally centered on the rational utilization of the in situ generated H-source (electrons) for hydrogenations, in which photogenerated holes were quenched by sacrificial reagents. Herein, the fully-utilization of the liquid H-source and holes during water splitting is presented for photo-reductive N-alkylation of nitro-aromatic compounds. In this integrate system, H-species in situ generated from water splitting were designed for nitroarenes reduction to produce amines, while alkanols were oxidized by holes for cascade alkylating of anilines as well as the generated secondary amines. More than 50 examples achieved with a broad range scope validate the universal applicability of this mild and sustainable coupling approach. The synthetic utility of this protocol was further demonstrated by the synthesis of existing pharmaceuticals via selective N-alkylation of amines. This strategy based on the sustainable water splitting technology highlights a significant and promising route for selective synthesis of valuable N-alkylated fine chemicals and pharmaceuticals from nitroarenes and amines with water and alkanols.
Rhodium catalysts with cofactor mimics for the biomimetic reduction of CN bonds
Chen, Fushan,Deng, Li,Dong, Wenjin,Tang, Jie,Xian, Mo
, p. 5564 - 5569 (2021/08/25)
A strategy based on the cooperation between metal and bonded cofactor mimics was applied to the transfer hydrogenation of CN bonds. We designed and synthesized a rhodium complex containing a 1,3-dimethylbenzoimidazole moiety, which could transfer hydride from a rhodium center to imine substrates in a biomimetic way. Under both transfer hydrogenation and reductive amination reaction conditions, the catalyst exhibited good selectivity towards CN bonds. With the catalyst, 34 imines were transfer hydrogenated to corresponding amines and a key intermediate of retigabine was prepared via reductive amination in a greener way. According to the NMR observations and isotope experiments, a plausible mechanism for this biomimetic reduction of CN bonds were proposed.
Hydrogenation and: N-Alkylation of anilines and imines via transfer hydrogenation with homogeneous nickel compounds
Benitez-Medina, G. Eliad,García, Juventino J.
, p. 17579 - 17587 (2019/12/23)
The nickel-catalyzed N-Alkylation of a variety of arylamines via transfer hydrogenation in the absence of pressurized hydrogen and basic or acidic additives was achieved in a tandem reaction. This process was further extended to the CN bond reduction and N-Alkylation of a variety of imines with ethanol, the latter acting as a hydrogen and acetaldehyde source, which allowed for the reduction and subsequent condensation to yield the corresponding N-Alkylated products.
N-Heterocyclic Olefin-Ligated Palladium(II) Complexes as Pre-Catalysts for Buchwald–Hartwig Aminations
Watson, Ian C.,Schumann, André,Yu, Haoyang,Davy, Emma C.,McDonald, Robert,Ferguson, Michael J.,Hering-Junghans, Christian,Rivard, Eric
supporting information, p. 9678 - 9690 (2019/07/09)
New N-heterocyclic olefins (NHOs) are described with functionalization on the ligand heterocyclic backbone and terminal alkylidene positions. Various PdII–NHO complexes have been formed and their use as pre-catalysts in Buchwald–Hartwig aminations was explored. The most active system for catalytic C?N bond formation between hindered arylamine and arylhalide substrates was accessed by combining a backbone methylated NHO with [Pd(cinnamyl)Cl]2 in the presence of NaOtBu as a base. In these active systems evidence suggests that catalysis is mediated by colloidal palladium metal, highlighting a different coordination ability of NHOs in comparison with commonly used N-heterocyclic carbene co-ligands.
An Efficient Metal-Free Method for the Denitrosation of Aryl N-Nitrosamines at Room Temperature
Chaudhary, Priyanka,Korde, Rishi,Gupta, Surabhi,Sureshbabu, Popuri,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
supporting information, p. 556 - 561 (2017/11/13)
A simple and practical method for the denitrosation of aryl N-nitrosamines to secondary amines is reported under metal-free conditions using iodine and triethylsilane. Several reduction-susceptible functional groups such as alkene, alkyne, nitrile, nitro, aldehyde, ketone and ester were found to be very stable during the denitrosation, which is remarkable. Broad substrate scope, room temperature reactions and excellent yields are the additional features of the current methodology. (Figure presented.).
Visible-Light Photocatalytic Synthesis of Amines from Imines via Transfer Hydrogenation Using Quantum Dots as Catalysts
Xi, Zi-Wei,Yang, Lei,Wang, Dan-Yan,Pu, Chao-Dan,Shen, Yong-Miao,Wu, Chuan-De,Peng, Xiao-Gang
supporting information, p. 11886 - 11895 (2018/09/25)
CdSe/CdS core/shell quantum dots (QDs) can be used as stable and highly active photoredox catalysts for efficient transfer hydrogenation of imines to amines with thiophenol as a hydrogen atom donor. This reaction proceeds via a proton-coupled electron transfer (PCET) from the QDs conduction band to the protonated imine followed by hydrogen atom transfer from the thiophenol to the α-aminoalkyl radical. This precious metal free transformation is easy to scale up and can be carried out by a one-pot protocol directly from aldehyde, amine, and thiophenol. Additional advantageous features of this protocol include a wide substrate scope, high yield of the amine products, extremely low catalyst loading (0.001 mol %), high turnover number (105), and the mild reaction conditions of using visible light or sun light at room temperature in neutral media.
Well-Defined Amidate-Functionalized N-Heterocyclic Carbene -Supported Rare-Earth Metal Complexes as Catalysts for Efficient Hydroboration of Unactivated Imines and Nitriles
Huang, Zeming,Wang, Shaowu,Zhu, Xiancui,Yuan, Qingbing,Wei, Yun,Zhou, Shuangliu,Mu, Xiaolong
supporting information, p. 15069 - 15078 (2018/12/14)
Four amidate-functionalized N-heterocyclic carbene (NHC) rare-earth metal amido complexes [(κ2-N,O-κ1-L)2REN(SiMe3)2] (L = 1-(C6H5CONCH2CH2)-3-(CH3)3C6H2(N(CH)2NC)) [RE = Er (1), Y (2), Dy (3), Gd (4)] were synthesized by one-pot reactions of 2 equiv of (1-(C6H5CONHCH2CH2)-3-(CH3)3C6H2-(N(CH)2NCH))Br (H2LBr) with 5 equiv of KN(SiMe3)3 followed by treatment with 1 equiv of RECl3 in tetrahydrofuran at -40 °C. These complexes were fully characterized, and their catalytic activities toward hydroboration of unactivated imines and nitriles were investigated, and it was found that these complexes displayed excellent activities as well as remarkable functional group compatibility for imine and nitrile substrates such as halo-, alkyl-, hydroxyl-, N,N-dimethylamino-, and nitro- substituents. Among those, the chemoselectivity for this reaction among the common unsaturated functional groups was achieved in the order CO CN > C=N > CO2Et > CC in the current catalytic system, which may facilitate their further application in synthetic chemistry.
Metal- and Base-Free Room-Temperature Amination of Organoboronic Acids with N-Alkyl Hydroxylamines
Sun, Hong-Bao,Gong, Liang,Tian, Yu-Biao,Wu, Jin-Gui,Zhang, Xia,Liu, Jie,Fu, Zhengyan,Niu, Dawen
, p. 9456 - 9460 (2018/07/29)
We have found that readily available N-alkyl hydroxylamines are effective reagents for the amination of organoboronic acids in the presence of trichloroacetonitrile. This amination reaction proceeds rapidly at room temperature and in the absence of added metal or base, it tolerates a remarkable range of functional groups, and it can be used in the late-stage assembly of two complex units.
C-N Bond Formation Catalyzed by Ruthenium Nanoparticles Supported on N-Doped Carbon via Acceptorless Dehydrogenation to Secondary Amines, Imines, Benzimidazoles and Quinoxalines
Guo, Bin,Li, Hong-Xi,Zhang, Shi-Qi,Young, David James,Lang, Jian-Ping
, p. 5627 - 5636 (2018/12/04)
Ruthenium nanoparticles (NPs) supported on N-doped carbon (Ru/N?C) were prepared by the pyrolysis of cis-Ru(phen)2Cl2 loaded onto carbon powder (VULCAN XC72R) at 800 °C. Ru/N?C NPs (0.2 mol% Ru) selectively catalyzed either acceptorless dehydrogenation coupling (ADC) or auto-transfer-hydrogen (ATH) reactions of amines with alcohols to imines and secondary amines. Such selectivity could be controlled by the choice of alkali metal ion associated with the base. Under similar catalytic conditions, the ADC cross-coupling of diamines with primary alcohols or diols afforded the corresponding benzimidazoles and quinoxalines in good to excellent yields. This catalytic system displayed good activity, recyclability, and wide applicability to a diverse range of substrates.
